Characteristics on the Extreme Value Distributions of Deepwater Design ave Heights off the Korean Coast

한국 연안 심해 설계파고의 극치분포 특성

  • 정신택 (원광대학교 토목환경도시공학부) ;
  • 김정대 (원광대학교 토목환경도시공학부) ;
  • 조홍연 (한국해양연구원 연안ㆍ항만공학연구본부)
  • Published : 2004.09.01

Abstract

For a coastal or harbor structure design, one of the most important environmental factors is the appropriate design wave condition. Especially, the information of deepwater wave height distribution is essential for reliability design. In this paper, a set of deep water wave data obtained from KORDI(2003) were analyzed for extreme wave heights. These wave data at 67 stations off the Korean coast from 1979 to 1998 were arranged in the 16 directions. The probability distributions considered in this research were the Weibull, the Gumbel, the Log-pearson Type-III, and Lognormal distribution. For each of these distributions, three parameter estimation methods, i.e. the method of moments, maximum likelihood and probability weighted moments, were applied. Chi-square and Kolmogorov-Smirnov goodness-of-fit tests were performed, and the assumed distribution was accepted at the confidence level 95%. Gumbel distribution which best fits to the 67 station was selected as the most probable parent distribution, and optimally estimated parameters and 50 year design wave heights were presented.

연안 및 항만구조물의 설계에서 심해 설계파는 매우 중요한 환경인자이다. 특히, 심해설계파고의 분포 정보는 최근 부각되고 있는 신뢰성 설계에 필수적인 요소이다. 본 연구에서는 한국해양연구원(2003)에서 제시한 1979년부터 1998년까지의 한국연안 67개 지점의 16방향별 최대 유의파 산출자료를 이용하여 극치분포 분석을 수행하였다. 특성분석에 사용된 극치분포함수는 Weibull, Gumbel, Log-Pearson Type-III, Lognormal 분포이며, 각 분포함수의 매개변수는 모멘트법, 최우도법 그리고 확률가중모멘트법으로 추정하였다. 또한, 극치분포함수의 적합성은 95% 신뢰도 수준으로 $\chi$$^2$및 K-S 검정을 실시하였다. 그 결과, 한국연안의 심해 설계파고는 Gumbel 분포형이 가장 적합한 모형으로 파악되었으며, 최적 추정된 매개변수 및 재현기간 50년에 대한 심해 설계파고 정보를 제시하였다.

Keywords

References

  1. 국립방재연구소 (1998). 강우분석 프로그램의 개발
  2. 김정대 (2003). 한국연안 심해파의 극치분포 특성. 석사학위논문, 원광대학교
  3. 수산청 (1988). 해역별(동해 ·남해) 심해파 추정 보고서
  4. 한국해양연구원 (2000). 해상파랑관측 및 조사
  5. 한국해양연구원 (2003).파랑모델 산출자료(http://wave.kordi.re.kr/)
  6. 해양수산부 (1997). 장기파랑(심해 . 천해)자료 통계산출 시스템 매뉴얼
  7. 해양수산부 (2000). 항만 및 어항 설계기준
  8. 해운항만청 (1988). 전국 항만 설계파 추산보고서
  9. Ang, A. H-S and Tang, W.H. (1975). Probability concepts in engineering planning and design. I, John Wiley and Sons, Inc. 274
  10. Goda, Y. (1988). On the methodology of selecting design wave height. Proc. 21st Int. Conf. Coastal Engineering, 899-913
  11. Goda, Y. (2000). Random Seas and Design of Maritime Structures. World Scientific
  12. Goda, Y. and Kobune, K. (1990). Distribution function fitting for storm wave data. Proc. 22nd Int. Conf. Coastal Engineering, 18-31
  13. Goda, Y., Konogaya, O., Takeshita, N., Hitomi, H. and Nagai, T. (2000). Population distribution of extreme wave heights estimated through regional analysis. Proc. Coastal Engrg., 1078-1091
  14. Greenwood, J.A., Landwehr, J.M., Matalas, N.C. and Wallis, J.R. (1979). Probability Weighted Moments: Definition and Relation to Parameters of Several Distributions Expressible in Inverse Form. Water Resources Research, 15(5), 1049-1054 https://doi.org/10.1029/WR015i005p01049
  15. Hogg, W.D. and Swail, V.R. (2002). Effects of Distribution and Fitting Techniques on Extreme Value Analysis of Modelled Wave Height. 7th International workshop on Wave Hindcasting and Forecasting Preprints, Banff, Alberta, Canada
  16. Hosking, J.R.M. (1989). The Theory of Probability Weighted Moments. Research Report RC12210, IBM T.J. Watson Research Center, Yorktown Height, New York
  17. Isaacson, M. and MacKenzie, N.G. (1981). Long-term Distri-butions of Ocean Waves. Journal of the Waterway Port Coastal and Ocean Division, 107(2), ASCE, 93-109
  18. Kite, G.W. (1988). Frequency and Risk Analyses in Hydrol ogy. Water resources publications
  19. Muir, L.R. and El-Shaarawi, A.H. (1986). On the Calculation of Extreme Wave Heights. A Review, Ocean Eng., 13, 93-118 https://doi.org/10.1016/0029-8018(86)90006-5
  20. Ochi, M.K. (1982). Stochastic analysis and probabilistic prediction of random seas. Adv. Hydrosci., 13, 218-375
  21. Rao, A.R. and Hamed, K.H. (2000). Flood Frequency Analysis. CRC Press LLC
  22. Swail V.R. and A.T. Cox (2000). On the use of NCEP-NCAR reanalysis surface marine wind fields for a long-term North Atlantic wave hindcast. J. Atmospheric Oceanic Technology, 17, 532-545 https://doi.org/10.1175/1520-0426(2000)017<0532:OTUONN>2.0.CO;2
  23. Vledder, G. van, Goda, Y., Hawkes, R, Mansard, E., Martin, M.H., Mathiesen, M., Peltier, E. and Thompson, E. (1993).Case studies of extreme wave analysis: a comparative anal-ysis. Proc. 2nd Int. Symp. Ocean Wave Measurement and Analysis, ASCE, 978-992